Abstract: A laser sensor holder apparatus for enabling a power sensor to be held in the path of a laser beam to measure the beams power comprises a base unit including a mounting frame, and translation stages to enable the movement of a sensor mounting plate to a desired position in the path of a laser beam. The apparatus is useful in measuring the power of a laser beam. Applications of the apparatus include its use in direct imaging systems whereby the previous method of manually holding a power sensor in the path of a class 4 laser and all of its inherent disadvantages may be avoided.

Abstract: A system and method for inspecting an image-producing display according to a predetermined footprint is disclosed. The system includes a platform fixed to a first multi-axis positioning unit for supporting the display. A sensing head is disposed in confronting relationship with the platform to detect light produced by the display. The sensing head is carried by a second multi-axis positioning unit. The system also includes a controller having outputs coupled to the respective first and second positioners. The controller is operative to generate control signals for manipulating the respective positioners and arranging the display and the sensing head into one or more relative orientations defining the inspection footprint.

Abstract: Apparatus for measuring power in a laser-beam includes a transmissive diffuser for diffusely expanding the laser-beam and a photon detector for receiving the diffusely-expanded laser-beam and generating an electrical signal in response thereto. Electronic circuitry including a microprocessor is provided for interpreting the electrical signal as a measure of power in the laser-beam. A display device is provided for displaying the interpreted signal.

Abstract: A low cost, low power photometric circuit suitable for use in a low end camera includes a first counter for counting successive pulses produced by a first oscillator having a substantially constant oscillation frequency and a second counter for counting successive pulses produced by a second oscillator having an oscillation frequency which varies in accordance with ambient brightness. The ambient brightness is judged according to outputs of the counters so that even if the oscillation frequency of the second oscillator varies only slightly due to a change in ambient brightness, the slight variation is easily detectable as an accumulated count value. Accordingly, costly, high-precision components are not needed. The low cost photometric circuit requires no microcomputer, analog/digital converter or comparator and can be fabricated in a single integrated circuit operated at a low voltage of 1V or less, and is thus suitable for incorporation into a low end camera.

Abstract: A laser test probe is configured to include an electronic probe and a pair of optical fibers. The electronic probe is a high speed transmission line that is used to provide the required bias signal, as well as an RF test signal, to a laser being tested. The optical fibers are used to capture the optical output signals from the front and rear faces of the laser. These optical signals are then analyzed by a measurement control unit to assess the performance of the device under test. In its most basic embodiment, the test probe can be used to identify lasers that exhibit an insufficient (in the extreme, non-existent) optical output signal.

Abstract: To measure the optical power level of light from an object to be measured, a bias section applies to a photo-detecting section such a reverse bias voltage as makes the current multiplication factor M almost zero to prevent the output current from flowing, and then applies such a reverse bias voltage as makes the M one or more to allow the output current to flow. A processing section determines an offset level from the output of a direct-current amplifying section during an offset data acquisition period that the M is almost zero. The time T0 from when the bias section applies to the photo-detecting section such a reverse bias voltage as makes the M one or more to when the reverse bias voltage is applied to make the M almost zero is determined to be a measurement state. The processing section measures the optical power with a clock faster than time T0.

Abstract: A light measuring apparatus comprises an oscillation circuit, a first delaying circuit for delaying an output waveform of the oscillation circuit in accordance with a peripheral brightness, a second delaying circuit for delaying an output waveform of the oscillation circuit for a predetermined period of time, and a brightness judging circuit for judging a peripheral brightness in accordance with outputs of the first and second delaying circuits.

Abstract: A moving body surface or paper web (1) to be investigated is irradiated at at least one irradiation site by 3 laser light sources of a surface structure measuring device (FOS1, FOS2). Reflected and scattered light is detected and evaluated in order to calculate ellipse points. An ellipse major axis ratio corresponding to a fiber orientation ratio, and a fiber orientation angle are calculated from the ellipse parameters thus obtained. Identical measurements and calculations are carried out periodically on an isotropic sample (NO) and a sample (Nx) having a fiber orientation similar to that of the body surface to be measured, in order to calibrate the measurements at the body surface (1).

Abstract: A light sensing apparatus for different control systems includes a photosensitive element which generates a light current depending on light incident thereto. A pre-circuit connected to the photosensitive element is operative for generating separate basic signals in response to the light current generated by the photosensitive element. Processing circuits connected to the pre-circuit are active simultaneously for converting the basic signals generated by the pre-circuit into conversion-resultant signals having different forms respectively. The conversion-resultant signals are outputted to the control systems respectively. At least one of the processing circuits may include an oscillation circuit which oscillates at a frequency depending on related one of the basic signals generated by the pre-circuit.

Abstract: A converter for providing an electrical signal according to the status of a light spot applied thereto, comprises: a sensor for sensing the light spot and generating a position current according to the position of the light spot sensed thereat; and an operating circuit for providing the sensor with an operating current when the light spot is sensed by the sensor and for outputting a status current corresponding to the operating current. The sensor comprises two electrodes each providing a current with magnitude determined according to the distance between it and the position of the light spot sensed thereat. The position current is obtained by subtracting the first electrode current from the second electrode current.

Abstract: A photodetection system that analyzes a luminous flux (15) received on a line (10). The photodetection system includes an opaque mask (4) provided with at least one aperture (6), placed in the vicinity of the line, driver (7) designed to rotate the mask, detector (8, 9) of an angular position of reference of the mask, a field lens (12) concentrating the luminous flux (16) crossing the line onto a photodetector (1), and a processing unit (3) connected to the photodetector, for analyzing the luminous flux to yield values for several points on the line.

Abstract: A measurement circuit having high dynamic range includes high-gain and low-gain amplifiers connected in parallel. A shunt feedback circuit is activated to prevent the high-gain amplifier from saturating when the magnitude of an input signal exceeds its dynamic range. The output of the high-gain amplifier is utilized to measure small input signals and the output of the low-gain amplifier is utilized to measure large input signals.

Abstract: An optical path degradation detecting device having a laser distance detector which uses a laser beam to detect the distance between two objects and which generates distance signals representative of the distance between the two objects. A first predetermined point signal is generated upon the distance signals being in a distance representative of a first predetermined distance or less, and a second predetermined point signal is generated upon the distance signals being in a distance representative of a second predetermined distance or less, wherein the second predetermined distance is less than the first predetermined distance. A fault signal is generated if the second predetermined point signal is generated within a predetermined time interval relative to the generation of the first predetermined point signal.

Abstract: A pulse laser system for providing precise control of laser pulse energy. A fast pulse energy detector having response time in the nanosecond or sub-nanosecond range provides an electrical signal representing pulse energy to a trigger circuit, which integrates the signal and triggers an electro-optic switch when the integrated signal reaches a predetermined level. The operation of the electro-optic switch trims a portion of the pulse energy so that the resulting pulse energy is maintained at a consistent and desired level. In a preferred embodiment, the electro-optic switch includes a Pockels cell and at least one polarizing beam splitter. In this preferred embodiment, an optical delay line provides additional time for the pulse trimming components to operate.

Abstract: The present invention is a system and method to expeditiously and accurately measure the luminance, weave, jump and flicker of an object so that the best luminance available for that object may be achieved by making adjustments to the light source, the reflecting surface and the like. A scanning light receiver which produces a two dimensional optical image of the object whose luminance is to be tested, is set up so that it may view a substantial portion of the object. The light receiver is connected to a analyzer and interface unit ("AIU") to which it sends an electronic image representing the reflected luminance of the object during each scan. The reflected light that is detected by the light receiver is then analyzed by the AIU to determine the luminance levels, weave, jump and flicker of the luminance across a substantial portion of the object by measuring the voltage of each pixel detected by the light receiver measured against the voltage produced by a black level.

Abstract: A relative angle detecting system permitting a wider range of detectable angles and offering a small detection error by using polarization and a virtual reality providing system using the same are disclosed. The relative angle detecting system includes a light source having a given polarizing direction and a light reception unit in which a plurality of polarization filters having different polarizing directions other than 90 degree and a plurality of light-receiving devices for receiving light passing through the filters are incorporated, and a relative angle is calculated on the basis of a combination of strengths of output signals of the plurality of light-receiving devices.

Abstract: An apparatus and method for the testing of materials by thermal oxidation is provided. The apparatus comprises a housing having at least one optic-isolated chamber. A photon counting photomultiplier and a heat source, for each optic-isolated chamber, are also provided within the housing. A cell, having a plurality of gas inputs and gas outlets, for holding a sample to be tested, is provided within the housing for each chamber. The gas inputs and outputs are distributed about the cell so as to disperse gas evenly about the material to be tested. The apparatus is used to count the number of photons which escape from a test sample as various oxidation conditions are employed.

Abstract: Apparatus for measuring power in a laser-beam includes a transmissive diffuser for diffusely expanding the laser-beam and a photon detector for receiving the diffusely-expanded laser-beam and generating an electrical signal in response thereto. Electronic circuitry including a microprocessor is provided for interpreting the electrical signal as a measure of power in the laser-beam. A display device is provided for displaying the interpreted signal.

Abstract: A photometric system for a photographic printing apparatus having an exposure device for projecting light traveling from a light source (21) through a mirror tunnel (24), along a projection path through a photographic film (2) to printing paper (3). An opening (24b) is formed in a side wall (24d) having a mirror surface for forming the mirror tunnel. The photometric system includes a photometer (60) disposed outside the mirror tunnel for metering only light entering through the opening (24b) from a region of the opening (24b) and a region displaced from the region of the opening (24b) toward the light source, and a reflection mirror (31; 71) for deflecting the light entering through the opening (24b) toward the photometer (60). The reflection mirror (71) is switchable between a first position for deflecting the light entering through the opening (24b) toward the photometer (60), and a second position for covering the opening (24b).

Abstract: A photovoltaic module capable of being oriented by hand with respect to the sun including an electrically activated liquid crystal display device for generating a visual informational display which indicates at least the power generating effectiveness of the module for its instantaneous orientation with respect to the sun, and an array of photovoltaic cells for generating a first power output for a load and a second power output for activating the liquid crystal display device and a third power output signal for the liquid crystal display device indicating the power generating effectiveness of the module.

Abstract: When incident light is incident to a photodetector, photoelectrons are emitted therefrom and then multiplied to output an electric current signal. This current signal is integrated over a predetermined period of time in an integrator to be converted to a voltage signal. This voltage signal is converted to a digital signal by an AD converter. This digital signal is supplied to a histogramming memory, which generates a pulse height distribution of voltage signal. Based on a pulse height distribution N(h) generated with incidence of measurement-object light to the photodetector, a pulse height distribution of single photoelectron events p.sub.1 (h) generated by a generator of pulse height distribution of single photoelectron events, and pulse height distributions of k-photoelectron events p.sub.k (h) (k=2, 3, . . .

Abstract: A device for sampling a section of a laser beam using an elongated reflective element that is moved in a main direction that corresponds to the direction of elongation of the element and in a direction perpendicular to the main direction. This sampling device forms a part of a laser beam analyzer and provides a small reflected beam segment to the analyzer that corresponding to the part of the laser beam that impinges upon the moving elongated reflecting element.

Abstract: When incident light is incident to a photodetector, photoelectrons are emitted and multiplied in each of incident zones whereby a plurality of current signals are output. These current signals each are processed to estimate a distribution or a mean value of numbers of photoelectrons generated in each incident zone. Then estimated based on the estimate values of respective incident zones is the number of photoelectrons emitted from the entire photoelectric conversion surface. In this way the intensity of incident light is measured with accuracy.

Abstract: A ray tracing method including the steps of: emitting a ray from a viewpoint, which is set at a predetermined position, toward a lamp; ray tracing a ray which has been stochastically selected as a ray which reaches a light source of the lamp; and analyzing at least one of illuminance at a predetermined position on a surface illuminated by the lamp, luminance at a predetermined position on a surface of the lamp, and a color state of the lamp.

Abstract: An analyzer for performing automated assay testing. The analyzer includes a storage and conveyor system for conveying cuvettes to an incubation or processing conveyor, a storage and selection system for test sample containers, a storage and selection system for reagent containers, sample and reagent aspirating and dispensing probes, a separation system for separating bound from unbound tracer or labeled reagent, a detection system and date collection/processing system. All of the subunits of the machine are controlled by a central processing unit to coordinate the activity of all of the subunits of the analyzer. The analyzer is specifically suited for performing heterogeneous binding assay protocols, particularly immunoassays.

Abstract: A photometric device includes a photoelectric conversion section to photoelectrically convert the light from an object, output circuits that output information from the photoelectric conversion section, a logarithmic conversion section that logarithmically compresses the output from the output circuit, and a correction section that corrects the output from the output circuit. The correction section corrects the output from the output circuit after it is logarithmically compressed by the logarithmic conversion section. It is possible to obtain accurate photometric results using the photometric device. A simple computation method is used without burdening the microcomputer and memory.

Abstract: A high speed, automatic calibration system of laser (or other light source) sensitometers capable of a wide range of power measurements, of densitometers and of other optical power measuring systems, and particularly to an automatic gain scaling circuit for use in the same. The system measures optical power incident on a photodiode detector in the course of calibrating or using a sensitometer and automatically and rapidly selects the appropriate gain for the operational amplifier. An automatic gain scaling function performed in gain scale logic rapidly selects the proper gain of a transimpedance operation amplifier operating as a current to voltage converter and delivers an analog voltage signal within a range between an upper limit and a lower limit. An over range error signal is generated in response to an upper out of limit signal generated at the minimum gain set by said gain scale logic.

Abstract: A photometry device provides accurate photometry outputs over temperature by correcting light sensitivity variations of a light receiving element due to temperature variations. The photometry device includes the light receiving element, a light sensitivity detection device and a light sensitivity correction device. A correction formula is determined from the outputs of the light sensitivity corrections device generated at a standard condition and a condition other than the standard condition. The light sensitivity correction device corrects the outputs of the light receiving elements based on the correction formula.

Abstract: A light measuring apparatus capable of measuring ambient light, flash light from a flash source directly connected to the light measuring apparatus and flash light from a flash source that is remote. A photoelectric sensor can convert the light into electrical signals when an operator starts a light measurement cycle. A flash light emission signal can be generated to a flash source. The computer circuit can process the light signals to determine the specific mode of operation of the light measuring process, and based upon that particular mode of operation to appropriately calculate measurement values.

Abstract: A light detecting device for reliably detecting weak luminescing at a random position in a predetermined spatial area. The light detecting device has a fluorescent fiber containing a fluorescent coloring matter and a flat or curved concentrator having a primary surface, on which the fluorescent fiber is fixedly arranged with the axis thereof in parallel relationship to the primary surface. A light receiving means is connected to at least one end of the fluorescent fiber.

Abstract: A system for receiving electromagnetic energy with reduced signal aliasing in the cross-scan direction. The system is adapted to be mounted on a spacecraft or an aircraft for movement over a surface in the cross-scan direction and has a sensor for receiving electromagnetic energy. The invention (10) includes an arrangement for directing energy to the sensor which has an astigmatic blur in the cross-scan direction which is effective to reduce aliasing of a signal transmitted or received by the system in the cross-scan direction of movement. In the illustrative embodiment, the invention (10) includes an array (20) of radiometric detectors. A reflective optical arrangement directs energy from a surface to the detector array. The optical arrangement includes at least one mirror (16) which has a small controlled cylindrical surface perturbation which introduces an astigmatic blur into the received image which reduces aliasing of the signal in the cross-scan direction.

Abstract: A detection system for detecting the emission (i.e., the fluorescence or phosphorescence) from a contaminant contained in a sample gas. In order to keep the optics of the system clean and maintain a high signal-to-noise ratio in the detected signal, the detection system contains a housing separated into illumination and sample chambers by an aperture-containing partition. A sample inlet port is connected to the sample chamber, and a purge inlet port is connected to the illumination chamber to direct the purge and sample gasses into their respective chambers. A vacuum system is connected to a vacuum port on the sample chamber to simultaneously draw the sample and purge gasses into their chambers through the inlet ports; the purge gas is then drawn through the aperture and into the sample chamber. Finally, both gasses are drawn out of the sample chamber through the vacuum port.

Abstract: A method of testing a DC coupled optical receiver is provided. DC light is superimposed on an optical signal, the power of DC light is changed to observe waveform at a light extinction level, and the measurement and the prediction of the bit error rate are performed. Similarly, in a multi-channel DC coupled optical receiver, DC light is applied to a channel to be observed, while signal light is applied to other channels to observe cross-talk.

Abstract: An illuminant discriminator distinguishes a range of separate illuminants, including high efficiency fluorescent lighting, by modifying the frequency response of a signal output from a photodetector. A switchable high pass filter coupled to the photodetector has a first filter section with a first cutoff characteristic selected to pass signal components due to various types of lighting including high efficiency lighting, and a second section with second cutoff characteristic that separates out the high efficiency components. The high pass output is processed by a log amplifier to develop flicker frequency harmonics that are distinguished as to source illuminant by comparator stages. Undersampling artifacts due to high efficiency lighting are present in the mixed illuminant spectrum when the first filter section is operative, and positively identified as high efficiency lighting when the second section is operative.

Abstract: A measurement apparatus and method for evaluating a light emitting device automatically measures a carrier-noise ratio, an optical modulation index, and a relative intensity noise of the light emitting device, and graphically displays the resulted data. The measurement apparatus includes a photo detector for converting an input light signal from the light emitting device to an electric current, a DC amplifier for amplifying a DC component of the electric current, a first analog-to-digital convertor for digitizing the output of the DC amplifier, a RF amplifier for amplifying a high frequency component of the electric current, a detector for detecting the output of the RF amplifier, a second analog-to-digital convertor for digitizing the output of the detector, a controller for controlling sequences of automatic measuring operations, a display device for displaying the characteristics of the light emitting device.

Abstract: An essentially non-intrusive laser power meter is described which is dependent on the reflection of a minor fraction of energy from a laser beam. A small beam splitter positioned on the periphery of the laser beam directs a small amount of the beam's reflected energy to a silicon photodiode. The output signal from the photodiode is then sent to a meter readout to indicate the beam energy.

Abstract: A modular optical power meter is provided which comprises a plurality of modules, each of which contains a matched, compatible set of elements consisting of a terminal connector, a source of optical power and a sensor for sensing optical power. These elements are configured for compatibility with each other and with the type of fiber optic system for which the particular elements comprising the module are intended for use. Each module can be separately calibrated and, upon insertion into the optical power meter's mainframe unit, automatically informs this unit of the module's optical characteristics. These modules are easy to use and avoid complications and errors in use. Errors resulting from temperature gradients also are eliminated because the source and sensor comprising each module always are maintained in close proximity to each other and are stored and installed as a unit.

Abstract: A photometering apparatus for measuring the brightness of an object to be photographed, includes a condenser lens having at least one aspheric lens surface for condensing a bundle of rays reflected from the object. A diaphragm is provided at a predetermined distance behind the condenser lens with respect to the object, and a split type light receiving device is provided behind the diaphragm to receive light which passes through the diaphragm. These elements satisfy the condition represented by the formula 0.3.ltoreq.L.sub.ASP /T.sub.L .ltoreq.0.7, wherein "T" represents the distance between the surface of the condenser lens nearer to the object to be photographed and the light receiving device, and wherein "L.sub.ASP " represents the reduced distance between the aspheric surface of the condenser lens and the diaphragm. The term "L.sub.ASP " is defined by the relationship L.sub.ASP =(d.sub.L /N)+d.sub.s, wherein "d.sub.L " represents the thickness of the lens, "d.sub.

Abstract: A method and apparatus for determining the quality of an illuminating device, such as an elongated lamp, that is useable with an imaging device, such as a scanner. Electrical power is supplied to the lamp so that it emits a light beam. The light beam is then measured and a determination is made as to whether the emitted light of the lamp is within one or more predetermined values, which include overall brightness, stabilized output power, and profile flatness values.

Abstract: The beam power of a laser beam is sampled by locating an elongate radiation conductive path across and substantially normal to the axis of the beam and detecting the light emitted at at least one of the ends of the radiation path, the radiation at the end of the radiation path being representative of the beam power of the laser.The radiation conductive path can be a glass rod but preferably the path comprises one or more optical fibres.

Abstract: A method and device for measurement of exposure times in optical devices are disclosed. Specifically, a measuring diaphragm plate and a mask plate are associated with a measurement path and a projection path of the optical device and include a plurality of corresponding measuring diaphragms and masks, respectively. A graticule having markings corresponding to the contours of the measuring diaphragms is provided in the projection path proximate the mask plate and conjugate to an intermediate image plane, and a motor for selectively positioning a measuring diaphragm on the measuring path is synchronized with a motor for positioning a corresponding mask on the projection path, such that a selected measuring diaphragm and its corresponding contour markings are simultaneously imaged at the intermediate image plane.

Abstract: A temperature control system has a light intensity detection device for providing temperature compensation in accordance with the variation in angle of incident sunlight. The light intensity detection device includes a photoelectric device having a light receiving surface and which produces an electrical output signal in accordance with the intensity of received light. An optical device is disposed between a light source and the light receiving surface. Incident light transmitted through the optical device is re-directed to the light receiving surface by a plurality of prism surfaces disposed on the optical device facing the photoelectric device. The prism surfaces may be concentrically arranged around the optical axis of the photoelectric device.

Abstract: In the method for measuring the illuminance of a vehicle lamp according to the present invention, an image of the light emitted from a headlamp and projected onto a screen is picked up for every pixel, by an imaging device, to detect a gradient of each pixel; an illuminance of the light incident upon illuminance sensors disposed in predetermined positions correspondingly to the screen is detected by each of the illuminance sensors; a function or correlation diagram showing the relationship between the illuminances and gradients is generated based on the gradients corresponding to as many illuminances thus obtained as the illuminance sensors; and the function or correlation diagram is used to detect the illuminance at a position on the screen, the position corresponding to the desired pixel.

Abstract: A method and system for on-site measurement of strobe light intensity on an aircraft is disclosed, including the steps of orienting a photometric sensor toward the strobe light on the aircraft to be measured and determining the distance between the strobe light and the sensor. When the strobe light is operated, the photometric sensor detects light intensity based on transmittance from the strobe light. The detected light intensity is correlated with the distance between the sensor and the strobe light to generate a data reading representing an estimate of light intensity emanating from the strobe light. Each of these steps is repeated to determine additional data readings representing estimates of light intensity for the same light. The data is then stored in a memory storage means, such as a computer, and then processed to determine the average value of light intensity for the strobe light.

Abstract: A combined ambient light magnitude and light source direction sensor controls the headlamps and cabin climate of a vehicle. The combined unit employs a photodiode having a predetermined spectral response and a diffuser which also has a predetermined spectral response, the spectral responses being combined to achieve an overall spectral response which corresponds to that of the human eye. With this arrangement, the headlamps of a motor vehicle are turned on and off under different ambient light conditions, in a manner which corresponds to the perception of the driver. In addition, a light modulator provides the combined unit with a sensitivity to the angular location of the sun with respect to the vehicle in which the unit is installed. Such angular sensitivity facilitates in determining the portion of the interior of the vehicle undergoing thermal loading by the sun, and facilitates a corresponding adjustment of the climate control system.

Abstract: A line frequency is determined by interleaved sampling of ambient light to obtain analog voltage samples at predetermined sampling rates associated with two or more line frequencies. Where there are two line frequencies, one method separates the first samples by a time period at least equal to an analog-to-digital conversion time, and less than the earliest time when a sample associated with one line frequency would coincide with a sample from the other. There are n samples per flicker frequency period and Q samples for each line frequency are taken. In a second method, a first common sample is taken for all line frequencies, and a condition characterized by simultaneous samples for different line frequency sample groups triggers a common sample for all line frequencies. For both methods, digital sample values one through Q-1 for each group are operated on to obtain a result, and then two through Q are similarly operated on to obtain a second result.

Abstract: The present invention is a system that uses a single channel light meter to measure the actual red, green and blue light output response curves of a CRT monitor to the range of possible input monitor code values for each color. A computer is used to transform a desired corresponding tone scale through the corresponding response curve to obtain a look-up table or video shaper that calibrates the monitor to the desired corresponding tone scale. The transformation includes obtaining a tone scale intensity value for each possible input value and searching the actual response values for a closest match. The input monitor code value used to obtain the actual response matching intensity for the possible input value is the calibrated value displayed by the monitor when an image includes the possible input value. The system is used throughout the life of the monitor to bring the monitor back to calibration as it changes.

Abstract: A spacecraft attitude sensor which determines roll/pitch angles of a spacecraft, is disclosed. Two light ray detectors are provided in a manner to be canted by a predetermined angle with each other. Each of the two light ray detectors defines a "field of view" light beam channel. A scan mirror is arranged to reciprocally rotate, about a pitch axis of the spacecraft, between two predetermined angles. The scan mirror is positioned in front of the two light ray detectors so as to swing the field of view light beam channel. A prism is provided in front of the scan mirror and deviates the field of view light beam channel so as to allow the scan mirror to scan the Earth across limbs thereof. The provision of the prism is able to increase the application of the sensor.

Abstract: An optical system for the attenuation of laser light for measurement purposes which includes four logical subassemblies including a first attenuator subassembly for the attenuation of high power laser light, a second attenuator subassembly for lower power attenuation of the laser light, a third lens subassembly for collecting beam size data simultaneously at multiple locations in space, and a fourth logical subassembly including a beam measuring assembly for recording the beam size data received from the lens subassembly for analysis of the beam characteristics. The first attenuator subassembly is provided with a pair of reflecting, opposed facing, fixed wedges. The reflecting wedges are selectively tilted to eliminate interference effects between their inward facing reflecting surfaces. The second attenuator subassembly further includes a pair of opposed facing and movable wedges arranged in series with a fixed filter.

Abstract: A light measurement device includes a photoelectric converter for receiving light from an object to be measured and converting the light to a measuring electrical energy in accordance with the intensity of the light, an offset amount measurement device for measuring the offset amount of the photoelectric converter, temperature measurement device for measuring a first temperature of the photoelectric converter when measuring the offset amount, and a second temperature of the photoelectric converter when measuring the light from the object, a memory device for storing a characteristic of the photoelectric converter with respect to temperature, correction amount calculation device for calculating a correction amount based on the characteristic, the first temperature, and the second temperature, and a light intensity calculation device for calculating a light intensity based on the measuring electrical energy, the offset amount, and the correction amount.